1. Field of the Invention
The present invention relates to barbells for use in weight-lifting, and, more particularly, to a new and improved method and apparatus for locking weights onto a supporting bar.
2. Discussion of the Prior Art
Barbell systems commonly include an elongated, cylindrical bar or handle onto which matching disc-shaped weights are placed at either end and releasably or permanently attached to the bar. There are elongated barbells which are designed for two-handed lifting and considerably shorter barbells which are designed for one-handed lifting, also known as dumbbells. In this application, the term barbell shall be used broadly to refer to both the one- and two-handed devices.
While solid, one-piece barbells are the most convenient, they are very expensive because, in order to have a variety of weights, it is necessary to have a large number of separate barbells. For this reason, barbell systems which allow a variety of separate weights to be attached to a single bar are very popular.
A variety of methods and apparatuses have been employed to releasably or removably attach weights to the handles of barbells. A typical apparatus includes an elongated, cylindrical bar, a hollow cylindrical handle placed over the bar and a pair of ring-shaped retaining members placed over the bar. A weight is slidably placed on each end of the bar between the handle and a retaining member. The retaining members each have a single bolt extending radially therethrough. The bolt has suitable surfaces on the head thereof to enable the user to hand turn the bolt. As the bolt is screwed or turned into the retaining member, the tip of the bolt extends inwardly from an inner surface of the ring-shaped retaining member and comes into contact with the bar. As the bolt is further tightened, the retaining member is held securely against the bar. The weight is thus held securely on the bar between the immediately adjacent handle and retaining member.
A second common system includes an elongated bar with a central handle portion and with an externally-threaded portion at either end of the bar. The handle portion has a greater diameter than the threaded portion. Loose weights are placed onto either end of the bar and large nuts with internal threading are screwed onto the bar to retain the weights between the nuts and the handle portion of the bar.
A third system for attaching disc-shaped weights to a barbell is disclosed in U.S. Pat. No. 1,672,944. This system includes a hollow, internally-threaded bar and a pair of screws with enlarged heads which may be inserted through the holes in the disc-shaped weights and screwed into the bar to secure the weights to the bar.
Another system, disclosed in U.S. Pat. No. 4,579,337, includes a bar with a series of circumferential grooves on each end thereof and a fixed, raised protuberance or lip on the bar adjacent to each of the innermost grooves. This system also includes a pair of locking members to be placed on the bar, with each member containing a pair of cylindrical members which are believed to be rotated relative to each other to allow or restrict steel balls to move freely within the locking member or to be restrained to be in engagement with one of the aforementioned grooves. As can be appreciated, this barbell system includes a fixed length bar which is much longer than necessary in addition to requiring a slow and cumbersome method of attaching the locking members to the bar.
Another system for affixing weights to a barbell is disclosed in U.S. Pat. No. 4,638,994. This technique includes a hollow, internally-threaded bar and a pair of locking pins having a head which engages with a flat locking collar designed to hold a ring-shaped weight against the hollow bar. The locking pin also includes a shaft having a spring-biased tooth which is yieldingly urged radially outwardly from the shaft to engage with the threads of the hollow handle. Thus, the pin can be quickly inserted into the hollow handle but must be screwed out of the handle to remove the pin.
It is believed that none of the prior art systems include the ability to quickly and securely connect weights to the bar and quickly disconnect weights from the bar nor do these systems have these features with the added convenience of a barbell system which does not extend longitudinally outside of the weights. It is against this background and to overcome the shortcomings of the prior art that the present invention has resulted.